Means for feeding fuel to internal combustion engines of the high compression type



1,835,487 T0 INTERNAL COMBUSTION ENGI NES Dec. 8, 1931. w. 'G. GERNANDTMEANS FOR FEEDING FUEL OF THE HIGH COMPRESSION TYPE Filed Sept. 25, 19242 Sheets-Sheet Dec. 8, 1931. w GERNANDT 1,835,487 MEANS FOR FEEDING FUELT0 INTERNAL COMBUSTION ENGINES OF THE HIGH COMPRESSION TYPE Filed Sept.23, 1924 '2 Sheets-Sheet 2 I Fy Z Bi" f a.

Patented Dec. 8, 1931 UNITED STATES PATENT OFFICE WALDO G. GERNANDT, OFSOUTH BEND, INDIANA, ASSIGNOR TO GERNANDT MOTOR CORPORATION, OF CHICAGO,ILLINOIS MEANS FOR FEEDING TO INTERNAL COMBUSTION ENGINES OF THE HIGHCOMPRESSION TYPE Application filed September 2 3, 192 Serial No.733,249.

This invention relates to means for feeding fuel to an internalcombustion engine of the high compression type, that isto say, an enginein which air is taken into the working 5 cylinder and compressed by thepiston therein so that the high temperature developed is suificient toignite the fuel which is injected at the proper time from a compressionchamber in which fluid products of combustion are trapped and thencompressed for the purpose of injecting the fuel that is passed into thecompression chamber or a fuel depository therein.

The objects of this invention include means for obtaining a highcompression engine of great flexibility, that is to say, one that isresponsive to adjustments arranged to vary the speed and power of theengine.

Another object is to obtain an engine which is adapted to use fuelhaving a low specific gravity such as kerosene, or distillate, although,it is to be understood that it is not limited to one particular type offuel.

Another object of my invention is to provide an engine which isrelatively easy to start, yet positive in its starting operations. Otherobjects will be apparent to one skilled in this art.

In order to carry out the objects of my invention, I utilize thefundamental idea of trapping some of the fluid products of combustion ina compression chamber, preferably closely adjacent the main cylinder andthen after passing the fuel to the compression chamber, or a fueldepository therein, to compress the products of combustion, and at theproper time in the cycle to connect the compression chamber with themain cylinder whereby the fuelis injected into the said main cylinder.

Sinoemy Patent #1,305,533, issued June 3, 1919, discloses the idea ofusing fuel prodnets of combustion for fuel injection purposes, my resentinvention is directed to an improved orm and specific arrangement forfeeding fuel to the engine cylinder through the utilization of fluidproducts of combustion.

My present invention will be best understood by reference to theattached drawings, wherein Figure 1 is a part sectional View through theengine showing my improvement.

Figure 2 is a part sectional view at right angles to Fig. 1, the sectionbeing taken through the fuel plug and compression chamher also showingthe cam arrangement and Figure 3 is a topview of the fuel plug with thecover removed.

Referring now to details wherein like numw bers refer to correspondingparts in the various views, 1 is an engine cylinder having a p'iston4therein. The piston 4 is connected by. a'connecting rod 3 to a crankshaft 2 which carries the usual fly wheel not shown. The

piston 4 has the usual piston rings 5 and the cylinder 1 a water acket6. The engine illustrated is of the two cycle type having an exhaustport 7, the air intake not beingshown,

although, a by-pass 8 is indicated for'passing V the air, which iscompressed in the crank case to the cylinder when the piston is atsubstantially the lowest part of the stroke. The piston 4 has a part 9cut away to deflect air from the exhaust port as the air comes from thebypass 8. The pocket 12 is formed in the upper part of the cylinder whenthe piston is in "its position of the highest compression. The

valve 10 held in position by a spring 11 is used in the head of thecylinder for the purpose of relieving compression at the time ofstarting the engine. Attached to the end of the cylinder, and in anysatisfactory manner,

* as by bolts 12 is a fuel plug-13, and arranged preferably tandem withthe plug 13 is a compression plunger 14, the upper end of which isshaped at 15 to form a fuel depository. It I will be seen that betweenthe end of the plug 13 and the end of the plun er, or fuel depository15, there is forme a compression chamber. As indicated in the drawings,the plunger 14, preferably works in a sleeve 16 constructed of suitablematerial and a gasket 17 is placed between the end of the plug 13 andthe sleeve 16. Extending longitudinally of the plunger 14 from thedepository 15 i a passage-way 18, and from the pasage-way 18, andsubstantially near the bottom theref is a cross bore 19. \Vhen theplunger is in the position shown in Fig. 1, the cross hole or bore 19 isthen in alignment with an opening 20 through the engine or the sleeve 16which establishes communication between the compression chamber and thepocket 12. The sleeve 16 is also provided with a hole or passage 46which communicates with the upper part of the pocket 12. The purpose ofthis hole will be later described.

By reference to Fig. 2, the relative position 2 between the cam 21 andt7 3 compression plunger 14, will be seen. The compression plunger 14 isheld in proper position through the medium of the aligning pin or screw22, the end of which operates in a slot 23, so that the alignment of thepassages 19 and 20 will be assured. The lower end of the plunger 14 issurrounded with packing 24, held in position by a gland 25. A spring 26is used to return the plunger 14, after the compression stroke has beencompleted, through the medium of the cam 21. The end of the fuel plug 13is preferably provided with a bushing 27 in which is seated a controlvalve 28 which is held by a spring 29 so as to normally close theopening into the compression chamber. The upper end of the plug 13terminates in an enlarged portion forming a chamber 30. Extending intothe chamber, from the body of the plug, is an injection plunger 31,normally held in upward position by a spring 32. On the end of theinjection plunger 31 is positioned the end of the lever 33, the otherend of which preferably engages through a socket connection with the endof a push rod 34, the other end of the push rod having operativeengagement with a pivoted lever 35 and is actuated by a cam 36. A fuelcavity 37 is formed between the ends of the plunger 31 and the valve 28;the fuel cavity 37 is connected by passage-ways 38 and 39 with the fuelchamber 30. An adjustable valve 40 is carried in the body of the plug sothat the inner end is positioned in the passage-way 38 and controls theori tice of this passage leading into the opening 39. The purpose ofthis arrangement will be presently described. A fuel intake pipe isfitted into the opening 41, leading to the fuel chamber and an over-flowpipe. is adapted to be connected by the point 42 to the fuel'chamber,the level of the fuel chamber being approximately as indicated by thedotted line 43. The manner of feeding fuel to the chamber 30 will not befurther described herein as any satisfactory means may be utilized. Thechamber 30 is covered by a cover plate 44 through the medium of screwsentering the screw holes 45.

In operation, the position of the main working piston and thecompression plunger are shown at about the time when the fuel beinginjected into the engine cylinder. Of course, it is to be understood,that the plunger 14 may be timed with respect to the main working pistonso that the fuel is injected into the cylinder to give the maximum powerfrom the engine. Assuming that the parts shown in Fig. 1, are in theposition as stated fluid products of combustion, which are compressed inthe compression chamber, force the fuel from the depository 15, formedin the upper end of the compression. plunger 14 through the bore 19 andthe opening 20, into pocket 12 where fuel is ignited by the highlycompressed air therein. As the cycle of operation continues, and the cam21 reaches the point 47, the plunger 14, moves downward until the upperend thereof uncovers the port 46, which port is held uncovered untilapproximately the point 48, on the cam is reached, when the cam producesa slight. upward movement of the plunger 14 thereby closing the port 46.During the interval of time, the cam is moving from point 47 to point48, fluid products of combustion at a relatively low pressure, ascompared with the pressure directly after ignition takes place, arepassed into the compression chamber and when the point 48 of the cam isreached, the compression chamber is cut off from the working cylinder.

During the interval of the time that products of combustion are beingtrapped in the compression chamber, it will be seen by referring to Fig.2, that the cam 36 produces an injection of fuel into the compressionchamber which fuel is received by the fuel depository formed at the endof the compression plunger 14. This injection of fuel takes place insubstantially the following manner: it being understood that the fuelcavity 37 is filled with fuel coming through the passages 39 and theorifice. or passage 38, in which the end of the needle valve 40 ispositioned. As the cam 36 suddenly forces the push rod 34 upward thelever 33, is actuated to force the injection plunger 31, downward,suddenly raising the pressure in the fuel cavity 37 to such a point thatthe control valve 28 opens sufficiently to pass a definite, quantity offuel into the compression chamber. The amount of pressure which can bebuilt up in the fuel cavity 37 and likewise the amount of fuel passed tothe compression chamber, is controlled by the adjustment of the needle40, which regulates the size of the by-pass opening by the end of theneedle valve. From the point 48 to about the point 49 there issubstantially no movement of the compression plunger 14, which onlybegins to move rapidly upward at and in proper timed relationship withthe main piston as has been previously described.

It will be apparent that Various changes may be made in the details, forexample, an auxiliary opening may be provided from the fuel chamber 30to a point closely adjacent to the end of the plunger 31 whereby fueling a main cylinder and a piston therein,

means for feeding fuel to said cylinder 1ncluding; a compression.chamber having a lun er therein with means for actuatin said plunger inproper time with respect to said piston, said plunger having alongitudinal passage and across bore leading from said passage to theperiphery of said plunger, said engine having two passage-Ways, one inalignment with the cross bore in the plunger when the plunger is at theend of its compression stroke, and the other opening into thecompression chamber when the plunger is at the end of itsnon-compression stroke whereby fluid products of combustion may enterthe compression chamber, the end of said plunger acting as a fueldepository and means for injecting fuel into said plunger depository atthe proper time as described.

2. In an internal combustion engine having a main cylinder and a pistontherein, means for feeding fuel to said cylinder including; acompression chamber having a plunger therein with means for actuatingsaid plunger in proper time with respect to said piston, said plungerhaving a longitudi-, nal passage and a crossbore leading from saidpassage to the periphery of said plunger, said engine having passage-wayin alignment with said cross bore in the plunger when the plunger is atthe end of its compression stroke and at least one other passage w'ayopening into the compression chamber when the plunger is substantiallyat the end of its non-compression stroke whereby fluid products ofcombustion enter the compression chamber, and means for passlng fuelinto said compression chamber at the proper time as described.

3. In an internal combustion engine of the compression chamber through apassageway leading thereinto and controlled by said valve, and operatingmechanism to actuate the plunger to compress the fuel in the fuelchamber rearwardly of the valve to open the valve to discharge the fuelinto the compression chamber.

' 4. 'In an internal combustion engine of the class described, means forfeeding fuel to the engine cylinder including an injection plug and acompression plunger arranged coaxially to and in tandem therewith so asto form a compression chamber between the two of them, said plugcarrying a fuel pressure control valve opening into the compressionchamber and timed Operating mechanism for building up fuel pressure onthe side of the valve opposite the compression chamber to open the valveto discharge fuel into the iliary plunger to build up pressure in thefuel chamber to open the relief valve to establish communication withthe compression chamber. Y

6. In an internal combustion engine of the class described, means forfeeding fuel to the engine cylinder including an injection plug andacompression plunger arranged coaxially therewith so as to form acompression chamber between the two of them communicating with theengine cylinder, in combination with-an auxiliary fuel chamber locatedwithin the plug and communicating with the compression chamber throughan outlet controlled by a valve responsive to the pressure -in the fuelchamber and a secondary plunger operable to compress thev fuel in thefuel chamber sufficiently to open the valve controlling the outlet intothe compression class described, means for feeding fuel to the'fi 'essioChamber bet een the end of the engine cylinder including aninjectionplug and a compression plunger having a fuel depository and acompression chamber be tween the two of them, said plug provided witha-spring-controlled valve and a positively actuated plunger forming afuel chamber between them communicating with the plunger and the plug,said compression chamber communicating with the engine cylinder througha passageway controlled by the plunger.

8. Mechanism for injecting fuel into an engine cylinder comprising, incombination with said cylinder, a fuel-feeding plunger, a

separate sleeve forming a cylinder for the plunger and formed with apassage into the engine cylinder, the plunger having a passage from itsend which registers with the passage through the sleeve at the end ofthe compression stroke of the plunger, and a separate plug at the end ofthe sleeve and cooperating with the sleeve and the plunger to define acompression space.

9. Mechanism for injecting fuel into an engine cylinder comprising, incombination with said cylinder, a fuel-feeding plunger and a separatesleeve forming a cylinder for the plunger and formed with a passage intothe engine cylinder, the plunger having a passage from its end whichregisters with the passage through the sleeve at the end of thecompression stroke of the plunger.

10. Mechanism for injecting fuel into an engine cylinder comprising, incombination with said cylinder, a fuel compression chamber communicatingwith the cylinder, a compression plunger operable to compress fuel inthe compression chamber and controlling the communication with thecylinder, a fuel chamber communicating with the compression chamberthrough a fuel controlled passageway and a fuel plunger positionedcoaxial to the compression plunger and operable to exert a pressure uponthe fuel in the fuel chamber to open a valve leading into thecompresison chamber to discharge fuel thereinto.

11. Mechanism for injecting fuel into an engine cylinder comprising, incombination with said cylinder, a fuel compression chamber communicatingwith the cylinder, a compression plunger operable to compress fuel inthe compression chamber and controlling the communication with thecylinder, a fuel chamber communicating with the compression chamberthrough a fuel controlled passageway and a fuel plunger arrangedco-axially to the compression plunger operable to exert pressure uponthe fuel in the fuel chamher to open a'valve leading into thecompression chamber to discharge fuel thereinto, said fuel plunger andcompression plunger operated in timed relationship and means regulatingthe admisi'son of fuel in the fuel chamber.

12. In an internal combustion engine having a main cylinder and a pistontherein, means for feeding fuel to said cylinder including; acompression chamber having a plunger therein with means for actuatingsaid plunger in proper time with respect to said piston, said plungerhaving a fuel depository in its end, means for trapping fluid productsof combustion in the compression chamber comprising intercommunicatingaxial and diametral bores in the plunger, and a passage between saidcylinder and said chamber uncovered by the plunger for establishingcommunicationbetweemthe passage and the

